Q: We are currently designing our new hospital to use a Category 6 horizontal and would like to use it for our cable TV from the telecommunications room (TR) out to the patient rooms. We would feed the TRs with a coaxial feed from the cable provider, and split out using a multiplexer (16 connections per mux). Basically, we don't want to run coaxial cable to the end user from the TR. Do you see a problem with this, like RF interference to other data cables?
via the Internet
A: Current wisdom for cabling is "home runs from the TR to the outlet" for all services. Last month, I addressed cabling within a new home and recommended 75-Ω coaxial cabling for satellite, community antenna television (CATV), and closed circuit television (CCTV) systems. This is in accordance with ANSI/TIA/EIA-570B-2003 Residential Telecommunications Infrastructure Standard.
This month, I am addressing the same issue, for the same services but in hospitals...and the standards (not I) offer a different answer. ANSI/TIA/EIA-568-B.1 does not recognize 75-Ω coaxial cabling for use in commercial buildings.
While this may seem puzzling to those not actually participating in the drafting of these standards, the reason comes down to a show of hands. TR-42.1 Subcommittee for Commercial Building Telecommunications is responsible for ANSI/TIA/EIA-568-B.1-2001 Commercial Building Telecommunications Cabling Standard. TR-42.2 Subcommittee for Residential Communications Infrastructure is responsible for ANSI/TIA/EIA-570-B. The ratio of twisted-pair cabling product manufacturers to designers is much greater in TR-42.1 than in TR-42.2. Hence, when votes are taken regarding allowing 75-Ω coaxial cabling in commercial buildings, the idea is rejected. But in TR-42.2, where the ratio is more balanced, the idea of 75-Ω coaxial cabling for satellite, CATV, and CCTV systems is accepted.
Is there a problem with using 75-Ω coaxial cabling in health-care facilities for satellite, CATC, and CCTV systems rather than the more-expensive Category 6 cabling? My personal and professional opinion: Unless you are required by contract to fully comply with ANSI/TIA/EIA-568-B.1, No!
Then, of course, there is the additional expense of the hardware to get the broadband signal coming in from the service provider onto the 100-Ω twisted-pair cabling for delivery to the television sets in the patient rooms.
Since not many (I could not find any) televisions have 8-pin modular connectors, then additional hardware is required to get the signal back onto a cable that can connect to the television.
Each piece of hardware adds another potential point of failure in what could simply be a piece of 75-Ω coaxial cable with an F-connector on each end.
Most physicians take the Hippocratic Oath when they enter practice. Registered Communications Distribution Designers (RCDDs) have Standards of Conduct that promote high standards of professional and personal conduct. Of the nine bullet points in the RCDD Standards of Conduct, I am most often drawn to number four: "Refuse to engage in, or countenance, activities for personal gain at the expense of my customers, my company, or my profession."
There are strong arguments for using baseband and broadband baluns for occasional video feeds in locations where twisted-pair cabling is available and suitable 75-Ω coaxial cabling is not. But if the cable runs are dedicated 24/7 to television sets in fixed locations to provide entertainment video and gaming for bed-ridden hospital patients, installing twisted-pair cabling and baluns is not logical.
TIA takes on health care
Health-care facilities can range from historical to the most modern structures. They vary in cleanliness, temperature, and size, and can be single buildings, campuses, or a combination of buildings joined by walk bridges. They typically are constructed in many phases over the course of many years.
TR-42.1 is developing guidelines, intended to be a supplement to ANSI/TIA/EIA-568-B.1, to provide a universal, generic telecommunications infrastructure for the health-care industry.
The guidelines will address both clinical and non-clinical applications, including:
• Voice, data, video including security, CCTV, and CATV;
• Mobile applications including nurse call and patient monitoring;
• Professional, patient, and asset tracking;
•Diagnostic imaging, pharma applications, telemedicine;
• Bioanalytical systems, life safety, lighting control;
• Master clock;
• Public network; and others.
I have reviewed a very preliminary draft of TR-42.1's working document and, wonder of wonders, 75-Ω coaxial cabling is proposed as a recognized cable type. They even note, "references can be found in 570-B." But this is a very early stage in the document's development, and logic may again fall prey to a show of hands.
The least you can do
Health-care facility administrators are very concerned with the spread of dust, dirt, and germs. Work with the facility staff to designate an entrance, elevator, and corridor not used by patients, visitors, or health-care workers but that can be used by cabling crews.
Here are some things that may limit the spread of dust, dirt, and germs during cabling placement and removal:
• Place adhesive floor strips outside the door to the worksite area to trap dust, and change these as they become worn;
• Use a high-efficiency particulate air (HEPA) filtered vacuum to clean the worksite frequently;
• Wet-mop the floor outside the door to the worksite daily;
• Shampoo carpets when the project is completed.
And here is how to deal with the trash generated during the project:
• Remove trash as it is created; do not let it mount up;
• Transport trash in containers with tightly fitting lids, or if you use wheelbarrows, cover the load with a wet sheet;
• Do not haul trash through patient-care areas;
• Remove trash after normal office hours through the designated entrance or set up a chute through a window.
Remember, the patients are not the only ones at risk when years of germ-laden dust is distributed by popping the corridor tiles and tossing cable in health-care facilities.
DONNA BALLAST is BICSI's standards representative, and a BICSI registered communications distribution designer (RCDD). Send your questions to Donna via e-mail: [email protected]